This entry analyzes the topic of happiness from several fields and viewpoints. It examines historical and modern perspectives on happiness, particularly within the realm of economics, and elucidates the interconnection between happiness and the social sciences, economics, and the environment. The initial phase examines the perspectives of utilitarian philosophers like Bentham and Mill on happiness, focusing on the assessment of happiness through the pleasure and misery derived from individual activities. Furthermore, contemporary methodologies for assessing happiness, such as “Gross National Happiness,” conceived at the behest of the King of Bhutan, are also examined. The Happy Planet Index, an index used to assess happiness, underscores that happiness is not linked solely to material prosperity but that elements such as environmental and ecological sustainability are significant. The index assesses national happiness based on parameters such as life expectancy, satisfaction, and the ecological footprint. This entry asserts that wealth and happiness do not always correlate, indicating that happiness may be elevated in prosperous nations that use fewer natural resources.